A few years ago, when most
of us were shooting with 35mm cameras, a 400mm lens was considered to
be a super telephoto, intended primarily for professional sports photography
or for wildlife work. Today, an increasing number of digital cameras
incorporate optical zooms that extend beyond a 300mm equivalent focal
length, including two models with a full 420mm reach. (Even longer equivalent
focal lengths are possible with digital zoom but that degrades image
quality.) As cameras with powerful zooms become increasingly common
and affordable, super telephoto photography is accessible even to those
on a tight budget.

That's great news for anyone who enjoys shooting sports, wildlife, and
performers on a distant stage, or any subject that's far from the camera.
Simply zoom in to take frame filling images of the pitcher at a junior
baseball game or a black bear lurking near the road in a park, for example.
With a 380mm or longer zoom setting you can often exclude distracting
elements such as other spectators or tourists. As you'll soon discover,
however, many handheld telephoto shots will not be sharp, particularly
those made at shutter speeds slower than 1/400 sec. That's because long
focal lengths magnify the least bit of camera shake, producing blurry
images.

There are two common methods
that we can use for making sharper images in low light. Mounting the camera
on a rigid tripod is ideal, but a tripod is impractical or prohibited
in many locations. The other alternative is to switch to ISO 400 or 800
for fast shutter speeds to "freeze" camera movement; if possible,
bracing your elbows on a firm support to maximize the odds of getting
sharp images. That combination of techniques can work well, but the images
will probably exhibit obvious digital noise, colored specks resembling
coarse film grain.

High Tech Feature For
Sharper Images
It's tough to get sharp images in handheld shooting with a long lens,
regardless of the type of camera that you use. That's why Canon, Nikon
and Sigma make some lenses for SLR cameras with a built-in "image
stabilizer" or camera shake compensation device. Such lenses are
expensive and available only for SLR cameras, but there's good news for
those who want a digital camera with a built-in zoom lens. You can find
several models that incorporate an image stabilizer, including the Panasonic
Lumix DMC-FZ10 that I tested, with its incredibly versatile 35-420mm (equivalent)
zoom, the most powerful built-in lens at the time of my tests. Other cameras
with image stabilizer are available as listed in the sidebar (below).

When
hand holding a camera, telephoto images made at long shutter
speeds are significantly blurred by camera shake, as in
image A. Brace your elbows on something solid and activate
the image stabilizer and you can make surprisingly sharp
images even in long exposures image B. (ISO 200; 250mm equivalent;
f/2.8 at 1/125 sec; OIS Mode 2; images slightly cropped.)

But should you pay extra for
a camera with a built-in stabilizer? How successful is the technology
and will it solve all of the problems that cause blurry pictures? In order
to answer those questions, I recently tested the 4-megapixel Panasonic
Lumix DMC-FZ10 with a "Mega Optical Image Stabilizer" or OIS.
This is a system that detects the angle and speed of camera movement with
a shake-detecting sensor and compensates by shifting an internal lens
element. Consequently, the light rays reaching the image sensor should
be stable instead of vibrating at the moment of exposure, increasing the
odds of a sharp image.

This Lumix camera was the first to offer a choice of two OIS options.
In Mode 1, the stabilizer is continuously active, providing "normal"
stabilizing that's suitable for most situations. Switch to Mode 2 and
the stabilizer is inactive until you press the camera's shutter release
button, which provides a "maximum" effect over camera movement
in any direction. Panasonic recommends Mode 2 for shooting at long exposure
times, in high magnification "macro" photography and when panning
with a moving subject at long shutter speeds.

Image Stabilizer Evaluation
In order to test the value of an image stabilizer, I shot hundreds of
pictures, with and without OIS, both indoors and out. Test subjects included
the competitors at the Canadian Aboriginal Festival, performing inside
a cavernous, dimly-lit arena, stamps and other small objects, as well
as people involved in outdoor activities. As per my findings listed here,
the OIS system was often beneficial, helping to solve technical problems
or providing greater versatility in the choice of camera settings that
would produce the best possible results.

In dimly-lit sections of the arena, for example, I found that the image
stabilizer was invaluable, especially for tight close-ups of distant competitors
who were far beyond the range of flash. I was able to make sharp 420mm
(equivalent) images at a shutter speed of 1/100 sec at f/2.8 using the
ISO 400 setting. For comparable sharpness with a non-stabilized camera,
a shutter speed of 1/400 sec would have been necessary, requiring an ISO
1600 setting. Such high ISO options are available only with D-SLR cameras
and generally produce images with excessive digital noise that degrades
fine detail. When I braced my elbows on a railing, I was able to get sharp
super telephoto shots using ISO 200 for even better image quality, at
a shutter speed of 1/45 sec.

Like any image stabilizer, OIS compensates only for camera movement and
not for subject motion. Consequently, my wide angle shots of fast moving
performers--in 1/10 sec exposures, using Mode 2 and ISO 100--exhibit
motion blur but their surroundings are sharply rendered. The overall effect
is quite pleasing, simulating flowing motion in a still image.

In outdoor photography the OIS system was not often necessary. In bright
conditions, the camera produced very fast shutter speeds even at the ISO
50 setting that I preferred for the best possible image quality. When
using a polarizing filter--to enrich blue skies or to wipe glare
from reflective surfaces--I simply switched to ISO 100 and made sharp
super telephoto images without OIS.

Overcast Days
During dark, overcast days or in the low light at dawn and dusk, OIS was
more useful, though not always necessary. Because the Leica lens features
an unusually wide maximum aperture of f/2.8, shutter speeds were often
quite fast at ISO 200. And yet, shooting at f/2.8 has two disadvantages,
particularly at long focal lengths. As with any camera, image quality
drops to acceptable, with softness outside the central area, and depth
of field--the zone of sharpness in an image--is very limited.
For these technical and aesthetic reasons, I often preferred to shoot
at f/8; that called for much longer exposures, making the image stabilizer
a valuable amenity when working without a tripod.

An
image stabilizer compensates for camera shake but cannot
freeze the movement of a performer, an active animal, a
competing athlete or flowing water. When shooting at long
shutter speeds, take advantage of the system to produce
interesting motion effects while maintaining sharpness in
surrounding areas. (At ISO 100; f/2.8 at 1/10 sec handheld;
OIS Mode 2; 35mm equivalent; image cropped.)

Close-Ups, Too
In extreme close-up photography, very high magnification is required to
fill the frame with a tiny subject, amplifying the effect of any camera
shake. When I used conventional cameras (handheld), fast shutter speeds
were required for sharp images in soft, cloudy daylight. (In extreme close-ups,
flash is generally impractical because of excessive intensity.) That called
for an ISO 400 setting or wide apertures--and inadequate depth of
field--at low ISO settings. The Panasonic OIS system solved this
problem, producing sharp images at a 100mm (equivalent) zoom setting at
shutter speeds as long as 1/30 sec in Mode 2. This enabled me to shoot
at ISO 100 at an aperture of f/5.6 for the best possible results.

The OIS Advantage
Here's the bottom line on the benefit provided by the Panasonic OIS system.
In handheld shooting, the Lumix DMC-FZ10 produced sharp images at shutter
speeds four times longer than a conventional camera. This offered greater
versatility in ISO and aperture (f/stop) selection, a valuable benefit
for any serious imaging enthusiast. The system was smooth and quiet and
it did not slow camera performance. Even with OIS fully active, I was
able to shoot a series of five full resolution JPEGs at a blazing 4 fps.
Granted, full-time OIS increased battery consumption by about 30 percent,
but I was able to shoot all morning during a parade without power failure.